细胞直接共培养模型在大鼠肺成纤维细胞转分化中的应用

目的:探讨细胞直接共培养模型在大鼠肺成纤维细胞转分化研究中的应用价值。方法:分离SD大鼠肺巨噬细胞和成纤维细胞,采用ThinCertTM进行共培养,并分为4组:对照组加入无SiO2粉尘的培养基,SiO2低、中、高剂量处理组分别加入终质量浓度为25、50和100mg/L的SiO2粉尘悬液,培养24h后,收集成纤维细胞和培养上清,分别采用real-time PCR检测成纤维细胞中α-平滑肌肌动蛋白(α-SMA)、Ⅰ型胶原(COLⅠ)及Ⅲ型胶原(COLⅢ)的mRNA水平,ELISA法测定培养上清中α-SMA、COLⅠ和COLⅢ蛋白。结果:SiO2处理组的α-SMA、COLⅠ和COLⅢmRNA和蛋白的表达水平明显高于对照组,且随SiO2质量浓度的升高,α-SMA、COLⅠ和COLⅢmRNA和蛋白的表达水平有升高的趋势(P<0.05)。结论:细胞直接共培养模型可用于大鼠肺成纤维细胞转分化的研究。     

IL-12与IL-18在体外培养系统中诱导肿瘤特异性CTL杀伤活性的比较

目的：分别应用重组人白细胞介素12（rhIL-12）及重组人白细胞介素18（rhIL-18）在体外培养系统(CCs)中诱导肿瘤特异性细胞毒性T淋巴细胞(CTL),比较IL-18与IL-12诱导的肿瘤特异性CTL的杀伤活性，探索IL-18的抗肿瘤作用机制。方法：采用Stem Sep^TM免疫磁性细胞分离法分离人外周血NK细胞、T细胞及DCs细胞，流式细胞仪分析细胞表型，¹²⁵I-UdR标记的细胞毒实验检测杀伤活性。结果：在CCs中、在肿瘤抗原存在的条件下，rhIL-18和rhIL-12均能诱导产生针对U251、MCF7特异性CTL，其作用能力与rhIL-18和rhIL-12的浓度呈剂量依赖关系，但rhIL-18诱导肿瘤特异性CTL的作用明显高于rhIL-12（P<0.01）；rhIL-18和rhIL-12在诱导肿瘤特异性CTL过程中具有协同作用，两者联合应用诱导肿瘤特异性CTL的能力明显高于单独应用rhIL-18和rhIL-12（P<0.01）。结论：rhIL-18和rhIL-12在CCs中均能够诱导并促进CTL介导的肿瘤特异性杀伤效应，rhIL-18诱导的肿瘤特异性CTL的能力明显高于rhIL-12，两者在诱导肿瘤特异性CTL过程中具有协同作用。     

联合培养的内皮细胞对平滑肌细胞增殖和形态的影响

目的探索体外培养和扩增同一来源内皮细胞和平滑肌细胞的有效方法,研究联合培养的内皮细胞对平滑肌细胞形态和增殖的影响。为研究内皮细胞和平滑肌细胞相互关系和体外构建组织工程血管提供理论和实践基础。方法在体外用酶消化法和组织块贴壁法分别建立内皮细胞和平滑肌细胞的原代,并应用胰蛋白酶和乙二胺四乙酸钠传代培养。应用光镜、透射电镜、细胞计数和MTY法对内皮细胞和平滑肌细胞的形态和代谢进行研究。模拟血管壁的内层结构及内皮细胞和平滑肌细胞间的相互影响途径,建立以聚对苯二甲酸乙二醇酯（PET）膜为介质的内皮细胞与平滑肌细胞联合培养模型。分3组：内皮细胞／平滑肌细胞、平滑肌细胞／平滑肌细胞和空白／平滑肌细胞,应用。H—TdR掺入法研究联合培养的内皮细胞对平滑肌细胞增殖的影响。结果酶消化法和植块培养法可以有效地建立起内皮细胞和平滑肌细胞的原代。内皮细胞对联合培养的平滑肌细胞早期增殖有促进作用,晚期则增殖缓慢。结论以PET膜为介炙联合培养同一来源的内皮细胞和平滑肌细胞的新模型是研究两者间相互影响的良好模型。内皮细胞和平滑肌细胞作为血管构成的基本细胞,对于它们的形态学、体外培养和扩增以及相互关系的研究具有重要的意义。     

嗅鞘细胞与大鼠尾状核神经元共培养的实验研究

目的观察嗅鞘细胞对大鼠尾状核神经元生长的影响.方法嗅鞘细胞与大鼠尾核神经元在无血清培养液中共培养,观察神经元生长变化.结果神经元与嗅鞘细胞共培养下神经元生长良好,轴突延长并形成网络状.结论嗅鞘细胞与大鼠尾状核神经元共培养可促进神经元生长.     

胚胎大鼠脊髓运动神经元与C2C12肌管体外共培养体系的建立

目的 获得胚胎大鼠脊髓运动神经元与C2C12肌管共培养的条件,在体外建立稳定的神经-肌肉共培养体系,并形成功能性的神经肌肉接头。方法 C2C12 成肌细胞株体外扩增培养至60%～70%融合时,用分化培养液诱导分化; 取孕15～16 d 的SD 大鼠,提取胚胎大鼠脊髓前角运动神经元细胞,种植到分化5 d的C2C12肌管细胞中,在神经元基础无血清培养液Neurobasal+2% B27中共培养。倒置显微镜下观察各个阶段神经元形态及突起长度的变化、肌管形态变化及收缩特性、神经肌肉接头的形成,应用免疫荧光染色技术检测突触后膜乙酰胆碱受体(acetylcholine receptor,AChR)特异性结合物α-银环蛇毒素(α-bungarotoxin,α-BTX),并采用屏幕录像技术记录共培养体系中肌肉收缩现象。结果 在共培养体系中,原代脊髓运动神经元与C2C12肌管细胞均能存活并进一步分化成熟。3 d时,可见运动神经元伸出的轴突延伸至肌管膜表面或包绕肌管; 1周时,肌管按同一方向排列,出现广泛的节律性收缩,同时免疫荧光染色结果显示α-BTX特异性结合突触后膜AChR; 共培养10 d 后,运动神经元开始凋亡,肌管细胞逐渐出现萎缩现象。结论 在体外培养条件下,无需特殊培养基和各种营养因子,运动神经元和骨骼肌细胞即可共同生存、生长并进一步发育,建立突触连接,触发一系列神经肌肉接头信号转导,引发肌管节律性收缩。     

Osteogenic differentiation of bone mesenchymal stem cells regulated by osteoblasts under EMF exposure in a co-culture system

This study examined the osteogenic effect of electromagnetic fields （EMF） under the simulated in vivo conditions. Rat bone marrow mesenchymal stem cells （BMSCs） and rat osteoblasts were co-cultured and exposed to 50 Hz, 1.0 mT EMF for different terms. Unexposed single-cultured BMSCs and osteoblasts were set as controls. Cell proliferation features of single-cultured BMSCs and osteoblasts were studied by using a cell counting kit （CCK-8）. For the co-culture system, cells in each group were randomly chosen for alkaline phosphatase （ALP） staining on the day 7. When EMF exposure lasted for 14 days, dishes in each group were randomly chosen for total RNA extraction and von Kossa staining. The mRNA expression of osteogenic markers was detected by using real-time PCR. Our study showed that short-term EMF exposure （2 h/day） could obviously promote prolifera- tion of BMSCs and osteoblasts, while long-term EMF （8 h/day） could promote osteogenic differen- tiation significantly under co-cultured conditions. Under EMF exposure, osteogenesis-related mRNA expression changed obviously in co-cultured and single-cultured cells. It was noteworthy that most osteogenic indices in osteoblasts were increased markedly after co-culture except Bmp2, which was increased gradually when ceils were exposed to EMF. Compared to other indices, the expression of Bmp2 in BMSCs was increased sharply in both single-cultured and co-cultured groups when they were exposed to EMF. The mRNA expression of Bmp2 in BMSCs was approximately four times higher in 8-h EMF group than that in the unexposed group. Our results suggest that Bmp2-mediated cellular interaction induced by EMF exposure might play an important role in the osteogenic differ- entiation of BMSCs.     

高温对体外培养大鼠海马锥体细胞凋亡的影响

目的探讨高温下新生大鼠海马锥体神经元凋亡形态学及生物化学变化。方法建立体外海马神经细胞培养模型,以37、40、42 ℃3种温度作为环境刺激因素,应用流式细胞仪、荧光染色、琼脂糖凝胶电泳和原位细胞凋亡检测试剂盒对其观察。结果随作用温度升高细胞凋亡率及凋亡小体数增加,电泳呈现DNA Ladder表现,荧光显微镜观察能够看到凋亡小体及其出芽现象。结论高温能够诱导体外培养的大鼠海马锥体细胞发生凋亡,且不同温度诱导其凋亡的程度及时程表现亦不同。     

软骨细胞与骨髓基质细胞共培养体外构建软骨的初步研究

目的 探讨不同浓度软骨细胞提供的软骨微环境诱导骨髓基质干细胞(BMSC)体外构建软骨的可行性。方法 将体外分别培养扩增的猪BMSC与耳软骨细胞按不同比例混合(9:1,8:2),均以5.0×107/mL的细胞终浓度接种于聚羟基乙酸/聚乳酸(PGA/PLA)支架作为共培养组,以相同终浓度的单纯软骨细胞和单纯BMSC分别接种作为阳性及阴性对照,以20％上述浓度的单纯软骨细胞接种作为低软骨细胞浓度对照。各标本于体外培养4周时取材,通过大体观察、组织学以及免疫组化等方法对新生软骨进行初步评价。结果 各组细胞均与材料粘附良好。8:2共培养组及阳性对照组在体外培养4周时,外观已类似软骨组织并基本保持了材料的大小和形状,组织学显示有较连续的成熟软骨形成,免疫组化也均显示有大量Ⅱ型胶原分泌。9:1共培养组在培养过程中稍有缩小和变形,组织学上仅在培养物的边缘可见到连续的软骨样组织。阴性对照组明显皱缩变形,组织学未见成熟软骨陷窝。低软骨细胞浓度组复合物明显变薄,只在局部形成了不连续的软骨组织,新生软骨量明显少于共培养各组及阳性对照组。结论软骨细胞能够提供软骨微环境诱导BMSC成软骨分化并形成软骨,20％浓度的软骨细胞已能够达到良好的诱导效果。     

人纤维环细胞与骨髓间充质干细胞Transwell共培养研究

目的探讨人的纤维环（AF）细胞与骨髓间充质干细胞（BMSCs）在Transwell共培养后,对AF细胞的细胞增殖和细胞外基质合成的影响,以及BMSCs是否具有向AF细胞分化的能力。方法分别对5例年龄在40岁以下脊柱手术患者的纤维环组织和骨髓标本进行分离、培养AF细胞和BMSCS,分别吸取第三代的AF细胞和BMSCs,按1 1的细胞比例分别植于Transwell共培养系统中,下室植入BMSCs,上室植入AF细胞。并且建立3个细胞培养组,即BMSCs与AF细胞共培养组（实验组）,BMSCs单独培养组和AF细胞单独培养组作为对照组。培养3周后,运用倒置相差显微镜观察细胞的形态变化;分别用HE染色、Ⅰ型胶原免疫组化染色和流式细胞仪对两种细胞鉴定;运用荧光定量PCR法检测各细胞培养组蛋白聚糖Aggrecan、Ⅰ型胶原蛋白mRNA及Sox9的表达变化。结果两种细胞在分离培养后经过鉴定确定为AF细胞和BMSCs。在倒置相差显微镜观察下,共培养组中AF细胞和BMSCs在细胞增殖数量和速度上均高于各自的单独培养组;共培养组中AF细胞和BMSCs的蛋白聚糖Aggrecan、Ⅰ型胶原蛋白mRNA及Sox9的表达均较各自的单独培养组高（P〈0.05）。结论通过BMSCs与AF细胞Transwell共培养,BMSCs可以促进AF细胞增值和细胞外基质的合成;同时通过共培养,BMSCs具有向AF细胞分化的可能。     

In vitro chondrogenesis of the goat bone marrow mesenchymal stem cells directed by chondrocytes in monolayer and 3-dimetional indirect co-culture system

Background  Cartilage injury has a very poor capacity for intrinsic regeneration. The cell-based treatment strategy for the cartilage repair using differentiated bone marrow mesenchymal stem cells (BMSCs) is, however, a promising approach to the chondral repair. This study was aimed to explore the chondrogenic potential of the goat BMSCs in the Transwell co-culture system and the poly-laetide-co-glycolide (PLGA) scaffolds.

Methods  The BMSCs were isolated from the goat iliac crest while the chondrocytes were obtained from the goat’s last costal cartilage. In the Transwell co-culture system, the BMSCs co-cultured with chondrocytes were designed as group A, whereas the goat’s BMSCs induced with the chondrogenic medium were group B. Both groups A and B were the experimental groups, while group C that only contained BMSCs was the control group. In the PLGA scaffolds co-culture system, BMSCs were seeded into the PLGA scaffolds, which were suspended in the 24-well plate, and the control group was established by presence or absence of chondrocytes at the bottom of the 24-well plate. Toluidine blue staining, Alcian blue staining, collagen II immunofluoresence, collagen II immunochemical staining, collagen I, collagen II, COL2a Q-PCR and osteopontin Q-PCR were used to examine the chondrogenic conditions as well as the expressions of chondrogenic and osteogenic genes.

Results  Cells isolated from the aspirates of the goat bone marrow proliferated rapidly and gained characteristics of stem cells in Passage 4. However, the differentiations of chondrocytes were not apparent in Passage 3. The results from Toluidine blue staining, collagen II immunofluoresence and PCR showed the transformation of BMSCs to chondrocytes in the Transwell co-culture system and PLGA scaffolds. Although the cartilage gene expressions were upgraded in both chondrogenesis group and co-culture system, the osteopontin gene expression, which represents osteogenic level, was also up-regulated.

Conclusions  The Transwell co-culture system and the PLGA scaffolds co-culture system can promote the chondrogenic differentiation of the goat’s BMSCs, while up-regulated osteopontin gene expression in the Transwell co-culture system implies the osteogenic potential of BMSCs.